This is completely done with base game as part of Ms Gryphi shell challenge. The rules given were as fallows: Place this shell and customize how you want. DO NOT DELETE WALLS. Also cannot delete the tree or the bookcase inside. Feel free to add walls, more floors, porches, etc. Just don't delete or move anything already placed down. You can find the origanal shell at #msgryphi #MsGryphiShell100k